Coil-retainer for dynamo-electric machines.



No. 879,949. PATENTED FEB; 25, 1908.

I G. DUNN. con RETAINER FOR DYNAMO ELECTRIC MACHINES.

APPLICATION FILED JUNE 3. 1907.

Fig. i.

\/T w I U! 9 WVifthesSaai Inventor,

. shown in one of the slots and locke UNITED STATES PATENT OFFICE.

GANO DUNX, OF EAST ORANGE, NEW JERSEY, ASSIGNOR TO (ROCKER-WHEELERCOMPANY,

' OF AMPERE, NEW JERSEY, A CORPORATION OF NEW JERSEY.

' Specification of Letters Patent.

Patented Feb. 25, 1908.

Application filed J'unc3- 1907. Serial No. 376.992.

To all whom it may concern:

' Be it known that I, GANo DUNN, a citizen of the United States ofAmerica, and a resident of East Orange, county of Essex, and State ofNew Jersey, have invented certain new and useful Improvements inCoil-Retainers for Dynamo-Electric Machines, of which the following is aspecification.

The object of this invention is to provide a device for securing thecoils or windings in the slots of dynamo-electric machine elements, thedevices being of simple construction and inexpensive material, easy ofapplication irrespective of the length of the slots, and reliable, soformed that they will not increase the self-induction of the windin s,will have negligible magnetic losses, wil be tree from eddy currents ofmoment, and will not obstruct the heat radiation.

In the accompanyin sheet of drawings which forms a part of thisapplication, Figure 1 shows a portion of the face of an armature with aslotted core in which windin s are with coil-retainers embodying myinvention. 'Fig. 2 shows a portion of the end of the armature with thecoil-retainers in edge view and the locked windingsin section. Fig. 3shows one form of such coil-retainer with narrow middle section drawn tolarger scale. Fi 4 shows a perspective view of a tool suitab e forapplying this form of coil-retainer. Fig. 5 shows another form ofcoil-retainer constructed to be locked by a tool with a screwdriver end.Fig. 6 is a persepctive view of a tool suitable for applying the form ofcoilretainer of Fig. 5.

The invention is illustrated in connection with an armature, the core ofwhich consists of circular iron punchings A with peripheral slots asshown. \Yhen these punchings are laid to other in sufiicient numbers theslots forme thereby have considerable length and in these slots thecustomary windings V are laid. In the side walls of each slot and nearthe mouth are notches n it into which the coil-retainers C-O lock. Thesecoil-retainers are conveniently punched from sheet metal. Metal isreferable to any vegetable fiber, because 0 the shallow space requiredabove the windings for a retainer of suificient strength. Metal ispreferable, also, because of ermanency of form, there being noshrinliing or loosening through drying, and it is less of an obstructionto the conduction and radiation of heat from the windin s. iron or brassis usual y to be preferred. Iron is the least expensive and it hasgreater strength and electrical resistivity, while brass, for example,avoids aslight increase in self-inductance which would-be. caused byiron. German silver, zinc and other metals may be substituted with someadvantages both as to dia-magnetism and electrical resistivity.

The invention is not to be regarded as limited. to any particular form,provided that it is constructed for insertion into the slot from theface instead of being slid in from the end, and is brought intoengagement by a tool which acts on the coll-retainer, preferably in arotative manner, to brin it into locking engagement with the notches inthe slot walls. Two forms are illustrated, a form C with a narrow middlesection and enlarged ends in Fig. 3, and a form C. like a frame with twodiagonal corners rounded and a rectangular centralopening, suited forengagement by a square ended tool or screw-driver. The form of Fig. 3affords less opportunity for circulatory currents, and is on thisaccount to be preferred. It is set in place by a tool T with doubletongues t t which engage either side of the narrow middle section. Theoutside dimension as taken on the axis (1-?) between inclosing parallellines is less than the width of the slot, and the outside dimension astaken on the axis cd is equal to the distance apart of the bottoms ofopposing notches in the slot walls. which lies intermediate of the othertwo axes, thc two diagonal corners of the coilretainer are'rounded so asto leave this dimension preferably slightly in excess of the distancebetween the bottoms of the notches so that the spring of the material ofthe armature core and of the coil-retainer will allow these corners topass the bottoms of the notches in revolving the coil-retainer, but suchexcess along this axis is not essential. The other two diagonal cornersare not rounded and prevent further rotation of the retainer after theaxis c-d' has been brought directly across theslot. A number ofcoilretainers are usually required in each slot at spaces generally fromtwo to six inches according to the weight and character of the windings,centrifugal ,force, width of the Of the metals,

On the axis ef slot, and bending :DIOIOIBBT, of the coil se teinersf Theslot insuietion may betui'ned down and folded over the windings prior tothe pressing down and engaging of the 500i retainers, in which case thenotches will he deer, or the coil-retainers may be inserted between thewefls of the siot lnsulation in Wiiicheese the coil-Ieteinersieedil'youtthis invention is not limited to the involving eieznents or armetures ofdirect current machines, nor to elements which have the siots for thewindings in their convex feces.

What I claim as new and desire to'secure hy Letters Patent of the UnitedStatesis:

1, The combination of e s1otteddynen1oeiectric machine element, windingslocated,

in the slot, and'a coih'eteinerconstrueted to admit of passage into theslot from the face of the element, end for-locking into the Walls of theslot by rotation, substantially as described.

ted impedes accidental nniockingof the emeee The eonihinetion of aslotted dynemoeiectrie machine element, the wens of the siotsneei thenmonths being notched, e -1ndings locsted in the slots, and acoil-nominee with" e middle section shaped for engagement with asnitebie key, the outside dimension along onesxis being less than theWidth of the slot, and the outside" dimension elong another. axis beingequal to the dis-= tense apart of the bottoms of opposhig notches,suhstentieily as described.

3. The combination of s siotted dynsnioelectiic machine element theWalls of the slots near their months being notched, Windings located inthe slots, and e coil-retainer having narrow middle section and enlargedends with the middle vsection shaped for engegement with e suitable key,the ontsiih dimension eiongone axis being less than the Width of theslot, and the outside dimension along another exisbeing equal to thedistance. apart oi the bottoms of opposing notches, substantially asdescribed.

Signed by me at Ampere, New Jersey, this 31st day of May, 1907. GANGDUNN 'Witnesses:

His-MW J. FULLERT B. HAnRIsoN.

